## Abs

### Instructions

Create a `isPositive` function that takes a number as
parameter and return true if the given number is
stricly positive, or false otherwise

Create the `abs` function that takes one number argument
and returns its absolute value.
You are not allowed to use `Math.abs`, make your own.


### Notions

- https://nan-academy.github.io/js-training/examples/functions.js
- https://nan-academy.github.io/js-training/examples/ternary.js
- https://devdocs.io/javascript/global_objects/math/abs


### Code provided
```js
Math.abs = undefined
```